


Zwischenzug

by kirstenlouise



Category: Sherlock (TV)
Genre: Bodily Fluids, Foot Fetish, M/M, Oral Sex, Sibling Incest, Watersports, Wet & Messy
Language: English
Status: Completed
Published: 2012-09-03
Updated: 2012-09-03
Packaged: 2017-11-13 11:35:44
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,811
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/503102
Author URL: https://archiveofourown.org/users/kirstenlouise/pseuds/kirstenlouise
Summary: <blockquote class="userstuff">
              <p>
  <i>Zwischenzug ([ˈtsvɪʃənˌtsuːk]; intermediate move): a chess tactic in which a player, instead of playing the expected move, first interpolates another move, posing an immediate threat that the opponent must answer, then plays the expected move.</i>
</p>
<p>"It's actually quite amusing," Mycroft says. He leans against the door frame and observes the Sherlock-shaped lump huddled beneath the blankets. "Seeing that you're the one who lost control of your bladder all over my favorite herringbone trousers. Yet, somehow, I'm still to blame."</p>
            </blockquote>





	Zwischenzug

**Author's Note:**

> This was originally intended to be a fill for [this prompt](http://sherlockbbc-fic.livejournal.com/19743.html?thread=118878239#t118878239), but as usual, I've rather wandered off-prompt. All my love to the kind, kinky anons who took a look at my first draft.

"We missed you at dinner."

"Sod off, Mycroft."

"It's actually quite amusing," Mycroft says. He leans against the door frame and observes the Sherlock-shaped lump huddled beneath the blankets. "Seeing that you're the one who lost control of your bladder all over my favorite herringbone trousers. Yet, somehow, I'm still to blame."

There's no indication that Sherlock has heard, but he knows the boy well enough to differentiate between the instances in which he's truly being ignored and those in which Sherlock only wants him to think he can't be bothered to pay attention. This is, without a doubt, one of the latter. Sherlock would never miss the chance to hear how one of his tantrums had been received.

"Mummy's all worked up," he continues, "thinking I've something terribly wrong with me. Medically, you know. She won't be pleased if she finds out you're in here having a sulk."

She'll be even less pleased if she ever finds out what he plans to do with Sherlock, but Mycroft keeps that to himself. Relations with Sherlock proceed, as ever, on a strictly need-to-know basis.

"You antagonized me," Sherlock mumbles. "You ruined my experiment. With malicious intent."

"Perhaps," Mycroft acknowledges, "but not by pissing on it."

"Might as well have done."

"I take it you won't be joining us for coffee in the sitting room, then. Shall I tell Mummy you're ill?"

"Tell her whatever you want."

***

Sherlock finds him relaxing in the garden with Goethe and a mug of tea the following afternoon.

"I've figured it out. Figured you out."

"Oh, yes?"

"At first I thought you were angry."

"You did ruin a perfectly serviceable pair of trousers," Mycroft remarks, without bothering to glance up. He hasn't been reading for the last half-dozen pages, but he continues to turn them, one after the other, in a perfectly-timed pantomime. Sherlock does so hate to be ignored, particularly by him. "Most people would be angry."

"I _thought_ you were angry," Sherlock repeats, voice strained, "but I was wrong. You enjoyed it."

"Is that a deduction or merely wishful thinking?"

Sherlock stares down at him contemptuously. Goethe goes the way of yesterday's trousers, tossed aside and in all likelihood ruined after its collision with his afternoon tea. Such a flair for the dramatic, his baby brother, and never willing to give an inch. Mycroft makes no move to stand, adjusting himself ever so slightly and letting his gaze stroke the placket of Sherlock's trousers. Sherlock flushes, predictably, and his mouth twists in an angry scowl---he hates to be found predictable even more than he hates to be ignored.

"You would have retaliated, if you were angry."

Mycroft shrugs. "Unless I was biding my time, waiting for the right moment to strike."

"You had ample opportunity."

"So you say."

Mycroft hardly pays attention to the dialogue, too focused on watching, waiting for all those tightly-held seams to unravel and burst open right before his eyes. Sherlock’s irritation is palpable, the crackle of electricity igniting the air around them. _Sturm und Drang_ , Mycroft thinks. Sweat beads on Sherlock's brow and the exposed curve of his neck.

He’s so painfully, dreadfully obvious in his anger. Mycroft would be ashamed to call him brother if it didn't make for such a delightful game.

"You enjoyed it, you pervert," Sherlock says, with absolute conviction. "You were half-hard in your trousers before I even finished. You didn’t even wash up after. I listened outside the bathroom door. Running the tap might have been sufficient to fool Mummy, but it isn't enough to fool me." He clucks in disgust. "Your sheets must reek of it."

Mycroft gives him a long stare of consideration. Childish, defensive, and more than a little amateur, but on the whole, quite correct. Mycroft mentally assigns him half marks for the effort.

"You'd let me do it again," Sherlock says.

Mycroft smiles. "Developing a taste for it, are you?"

For once, Sherlock declines to answer, though the twitch of his hand, ever so slightly toward his flies, is answer enough. It’s almost too easy, but Mycroft is lazy with the summer heat and craving the indulgence. Easy or not, the results have been more than satisfactory thus far.

He had been pleasantly surprised the evening prior, when Sherlock had backed him into a corner, murder in his eyes and all of him thrown into vibrating rage. His cock swells at the memory of it, Sherlock's hand braced on his chest and the other tugging out his prick, pink and soft and lovely, before he’d aimed it at Mycroft's trousers and soaked him with a hot stream of piss that he trailed all down Mycroft's trouser leg, where it had soaked into his socks and finally into the hall carpeting.

Mummy had caught them half a second after Sherlock had tucked his cock back into his pants and shrieked.

"Mycroft had an accident, Mummy," Sherlock said, smug.

It hadn't been far from the truth. It had been an accident. Oh, letting the air into Sherlock's fermentation chamber had been entirely deliberate, if not painstakingly calculated, but _exposing_ himself, to Sherlock of all people, had been completely unintentional. Of all the possible outcomes Mycroft had anticipated, the reality ranked rather far down on his list. Not that he was complaining, mind.

Sherlock shifts his thighs apart with a bare foot. "Did you masturbate after?"

"Did you?"

"Quiet."

He says it so viciously, Mycroft feels obligated to humor him. He hasn't quite let go of the hope of a repeat performance, even factoring in the inconvenience of Sherlock having discovered his dirty little secret. Even after years of practice, Sherlock shows far too much on his face, and Mycroft can follow his thought process as easily as if it were being diagrammed before his eyes, greedily taking in every micro-expression and shift in posture. Mycroft knows that face every bit as well as his own. There is no secret Sherlock can keep from him.

When Sherlock pulls out his cock this time, it's more than a little swollen. He can see a soft roundness to Sherlock’s belly where his shirt leaves him exposed. 

"You must be incredibly full," Mycroft remarks. "You've not gone since last night, have you? It must ache _terribly_."

At the word, the tiniest bead of fluid dribbles out of Sherlock's cock, leaving a damp spot on Mycroft's leg.

"Let's have it, then. We wouldn't want you to mess yourself, now, would we?"

Sherlock gives a quiet whimper before the floodgates tear open in a violent gush. His trousers only get a sprinkling this time, the bulk of it splashing onto the crisp, tailored linen of his shirt. Trickles of piss are diverted around Mycroft's collarbones and down his sternum in swirling eddies. It seems to go on forever with Sherlock wavering on his feet, pulse after pulse hitting Mycroft's front.

He slumps forward at the last, catching himself on the lattice and bringing his cock flush with Mycroft's face.

Mycroft leans up to take it in his mouth, forcing Sherlock to throw out his other hand to steady himself as Mycroft suckles at the head of his cock, tasting while the mess of his shirt grows tepid next to his skin. He curls a hand around the back of Sherlock's thigh, keeping him close, and gives an encouraging squeeze. He's rewarded with the barest trickle of hot fluid on his tongue and a pained noise from Sherlock as he forces the last bit of it free. 

That Sherlock has never had anyone's mouth on his cock is obvious. Mycroft had known it long before he ever set foot in the garden. His thighs are quivering in Mycroft's hands, his hips jerking unevenly against Mycroft's face. He gags slightly when Sherlock bumps the back of his throat, before managing to relax his throat and tighten his grip. Sherlock will be wearing bruises under his trousers tomorrow, Mummy none the wiser, but that’s the least of Mycroft's concerns.

It takes hardly any time at all before Sherlock is spurting into his mouth. Mycroft swallows greedily, licking him clean as best he can before Sherlock shoves off of his shoulders and stumbles backwards. The time ticks by in Mycroft’s mind. By his count, it takes Sherlock nearly thirty seconds to maneuver his prick back into his pants and fasten his zip before he slinks back into the house without another word.

Once he’s disappeared from view, Mycroft closes his eyes and lies down in the grass, peeling the hem of his shirt aside so he can slip a hand into his pants. He curls his fingers around the damp length of his cock, the taste of Sherlock lingering in his mouth as the last of the afternoon sun dries him.

_Check_.

***

It takes all of three days for Sherlock to come crawling back to him, ready to do more than shuffle pawns.

He's taking a bath, eager for a soak despite the heat, with his feet braced up on the wall of the tub. His legs are too long for anything else, but the warm water is a balm to his shoulders, stiff after a morning of tennis with Mummy. The steam has barely begun to dissipate when Sherlock starts pounding on the door in what Mycroft must grudgingly admit is perfect 6/8 time.

Mycroft sinks lower into the water to drown him out, only coming back up when Sherlock has stopped his siege symphony in the key of brat major. He perks his ears up and listens, for anything, certain that Sherlock is still lingering in the hall, and wondering if he really intends to wait for permission or if impatience will push him to lock-picking. He’s got frightfully good at it over the course of the summer.

"Mycroft," Sherlock says, "I have to use the toilet."

"The orchids were looking particularly parched yesterday, if memory serves."

"I’m not going to piss in the garden."

"And what’s wrong with the downstairs?"

A pause. "It’s being cleaned."

Mycroft snorts. "Yes, I’m sure."

"Please, I can't wait any longer. I---I think I might wet myself if you don't let me in." There's a thunk as Sherlock slumps against the door. He gives a despairing moan, followed by a hiccup that can’t possibly be a sob, though Sherlock can be incredibly convincing when he tries. "Please, Mycroft, I've already leaked a little."

_You dreadful tease_. "Oh, all right then. I'll only be a moment."

He takes his time getting out of the bath, not bothering to towel off or cover up. He lingers at the threshold of the door to see if any other delightful confessions will be forthcoming. It wouldn't do to have the poor boy piss himself all over the carpets like an ill-behaved puppy, even if turnabout is fair play, but Mycroft isn't above dragging it out a bit longer. He counts to five before letting Sherlock in, doing his best to keep the smile off his face as Sherlock elbows past him to the toilet and immediately drops his trousers. 

Mycroft admires the view of Sherlock’s arse, pert and milky white, as he closes the door.

Sherlock huffs impatiently. " _Mycroft_."

"Oh, I’m terribly sorry. Did you need a hand, brother?"

He doesn't wait for a response, although he's sure that whatever Sherlock has in mind would be equal parts petulant and delightful. He folds himself against Sherlock's back, kissing the side of his neck and wrapping a hand around his cock. Flaccid, again, though it doesn’t require any great stretch of the imagination for Mycroft to guess what he gets out of it, aside from the pleasure of the game; latent alpha male tendencies and an urge to mark one's territory, such as it is.

Mycroft fondles Sherlock as he grinds his cock between the boy's buttocks, slippery with sweat from the humid air. His mouth waters at the thought of how ripe and rich he must taste, but there’s time for that, and more, later. Mycroft draws back his hand and spits onto his fingers before bringing them back to trail saliva over the head. He rubs it into the slit with his thumb, the slight touch of wet coaxing a sympathetic spurt out of Sherlock’s cock.

Sherlock is trembling with the force it takes to hold the rest of it back as Mycroft thumbs gently over his slit, back and forth with a methodical, unrelenting slowness. It must be maddening, but Sherlock doesn’t say a word as his head drops back against Mycroft's chest. His eyes are closed, his lower lip wet with the touch of his tongue as Mycroft continues to tease him, letting his nail catch ever so slightly.

The pressure proves to be too much. 

Sherlock moans, cheeks suffused with red, and erupts all over Mycroft's hand. He jerks Sherlock’s cock slowly as the boy pisses, heedless of the erratic splashing it causes. He’ll right the havoc he’s wreaked of Sherlock’s aim later. Mycroft pulls and pulls until he's wrung the last drop out of him and Sherlock is plumping against his palm. He could come like this, his erection nestled against Sherlock’s bare arse, he supposes, and watch his filthy joy run down the backs of Sherlock's pale thighs. Mycroft’s cock throbs at the thought. 

But he won't, not yet. Not when Sherlock expects it. Instead, he tucks Sherlock back into his pants, taking a moment to palm him and smiling at the damp circle where he's leaked through them, and pulls up his trousers.

"Go on, now. I’ll be finished soon." 

***

Mycroft waits until Mummy has retired for the evening before he wanders into Sherlock’s room. He finds the boy with his nose buried in one of those pulpy detective novels he loves. Loves to tear apart, at any rate. All of Sherlock’s books are cluttered with biting marginalia engineered to deliver optimal wit per word.

He smiles inwardly as he takes a seat at the foot of the bed and lets his hand settle on Sherlock's knee. Aside from a faint tremor---it can’t be surprise; anticipation, perhaps?---Sherlock is utterly still as Mycroft works his way down one trouser-clad calf. He draws circles around the sharp little ankle, feeling the delicate boning beneath the skin before sliding his hand round to the sole.

"Any good, the mystery in this one?"

"Predictable. Metallic poisons. Quite amateurish."

"Ah."

Sherlock’s toes curl against his hand when Mycroft begins to massage the arch. His enthusiasm for the exercise is plain. Mycroft is willing to wager it might even be _palpable_ , judging by the hard in and out of breath through Sherlock’s nose, the kind that tells him Sherlock has his lips locked in one tight line. And all that at only his bare hands. He can only imagine how pliant a drizzle of something fragrant would make Sherlock---warm sandalwood, or a touch of indolent lavender.

Sherlock’s eyes are alight with lust. "Is this another fetish of yours?"

"I think you'll find the word is 'paraphilia', but no, I've no particular fondness for your feet. However---" he digs his thumbs into Sherlock's instep, eliciting a groan the boy tries valiantly to choke back---"I could be _quite_ amenable, given sufficient encouragement. Should you express willingness to accommodate me, shall we say, I would be more than happy to repay you in kind."

Though Sherlock takes great pains to render his face impassive, his pretense is spoiled by the hand already toying with his zip. It’s a painfully clumsy mistake and, under ordinary circumstances, Mycroft would be inclined to chastise him, but given the circumstances, he declines to comment. He’s grown tired of the chase. Let Sherlock disband with it if he likes.

"What sort of… accommodation are you after?"

Mycroft smiles. "Don’t worry. I’ll leave you with your virtue intact." 

As intact as it ever was, in any event.

"I want your mouth," Sherlock blurts out, before Mycroft has a chance to make a more substantial offer. "Not on my prick. You have figured it out, haven’t you?"

"Yes, I think you’ve rather shown your hand there."

His indignant scowl is everything Mycroft could have hoped for, but it slides right off his face again the moment Mycroft hooks a hand behind his knee. As prices go, it’s a small one to pay for what he intends to ask, and it’s rather charming, actually, the way Sherlock sets his toes _en pointe_ as Mycroft raises them to his mouth. He certainly can’t deny the thrill that comes with Sherlock tugging at his prick as Mycroft kisses the ball of his foot with the slightest hint of tongue along the ridge. Emboldened, he sucks a long toe into his mouth. Sherlock jerks as if he’s been prodded with a hot iron, his back arching off the bed before he collapses again with a whimper.

The red from Sherlock’s cheeks bleeds all the way down his pale chest, heaving with every lungful of air.

"Let me," he says, breathless. He swings his other foot onto Mycroft’s lap, his toes wriggling up between Mycroft’s thighs to press at his erection. "Take your prick out."

Curiosity prompts him to comply. Sherlock gives a contented sigh as he digs his toes lightly into Mycroft’s pubic hair, the heel of his foot surprisingly smooth and supple against the shaft of his cock. What a sight they must be---Sherlock slapping his cock against his belly, one wicked little foot held high for Mycroft to suck at and Mycroft’s prick throbbing against the sole of the other. Would he like it, if Mycroft came like this? Would he relish the squish of Mycroft’s come between his toes, slipperiness drying into tackiness?

Sherlock gives a pitiful moan as he comes, his heel jammed between Mycroft’s legs just this side of pain. Mycroft files the image away for another time and gives the sole of Sherlock’s foot a final kiss before letting his leg fall. He takes a moment to admire the come on his brother’s shirt and the sweat slicking his curls to his forehead before he begins to undress.

Sherlock’s post-orgasmic haze takes on a faint glimmer of disgust. "You never said---"

"I never ruled it out, either."

"You certainly implied it."

Mycroft shrugs out of his shirt. "Did I?"

"I won’t get hard again," Sherlock says. Mycroft can’t help but laugh at that, even when he insists. "I won’t, Mycroft."

"Oh, please. At your age, a stiff breeze would suffice. Anyway, I don’t need you hard for long. I wouldn’t expect you to proceed to climax. Alhough," he says, with a wry smile that only makes Sherlock’s scowl deepen, "I won’t object if you find it to your liking. Now, if you could kindly move aside, I’d like to lie down for this."

Sherlock budges over with a look that says he’d very much like to shove Mycroft to the floor. It’s half an act, of course, the way Sherlock’s disapproval always is. He’s never been fond of seeming overeager, always so desperate to pin what he wants on the most convenient scapegoat.

"Come here," he says, once he’s settled. "Just between my legs, that’s it."

"I never took you for the sort to like a cock up your arse."

"Well, then you weren’t paying much attention, were you?"

For all his protests, Sherlock looks perversely comfortable lying against his chest with his soft, sticky cock wedged between them and his fingers plucking at tufts of Mycroft’s chest hair. He’s only bothered to push his trousers down to his knees, the lazy thing, but no matter. Mycroft cups his bottom, soft and round, unable to resist giving Sherlock a bit of a smack.

" _Monster_."

"Oh, _honestly_ ," Mycroft laughs. He has half a mind to kiss away the disdainful little moue on Sherlock’s lips, but he has a feeling Sherlock would rail even harder against the idea that this might somehow be the product of intimacy and not something baser. Instead, he tilts his hips up into Sherlock’s so that his cock slips along Mycroft’s own. "Like this. Just until you’re up to the task, of course. I know how distasteful you find me."

The dig is lost on Sherlock, his hips already moving. It takes no time at all before his cock is swelling alongside Mycroft’s, his breathy moans and choked little grunts audible against Mycroft’s neck, if only just, each one a secret pitched for Mycroft’s ears alone. It’s not long before he feels the blunt pressure of Sherlock’s cock driving into his arse without finesse or any particular care for his comfort, though Mycroft had expected that. He likes the stretch, such as it is, and Sherlock is hardly in any position to be practicing restraint. Mycroft spreads his legs wide and lets Sherlock rut a few moments longer---he’s an eager pupil, if nothing else.

"Sherlock?"

He moans and gives a sharp shove of his hips.

"Sherlock," Mycroft repeats, more sternly.

Sherlock whines. "You said I could, if I liked it."

"After," Mycroft says. "But you need to take care of me first."

At last, it comes, barely a trickle at first, with a grunt that tells him all he needs to know, which is that Sherlock is still stiff inside him and he’s pushing through it.

Mycroft closes his eyes and takes himself in hand as the trickle becomes a steady, hot stream, pouring on the sheets as Sherlock empties his bladder into Mycroft’s arse. He moves his fist in quick, hard strokes, not wanting Sherlock to finish before he can. He’s hardly touched himself in the four days since Sherlock pissed on him in the garden and his cock feels fit to burst. He’s messing his hand before he knows it, the two of them entwined and panting. 

Why, one would almost think there was some affection there, in the way Sherlock clings to his side like a hot, sticky little animal, his leg hooked high on Mycroft’s hip to keep him stuffed after he’s spent himself. The mess oozes out around the perimeter of Sherlock’s soft prick as he twists his fingers in Mycroft’s chest hair.

"I suppose that’s game, set, and match," he says, after a time. "What does that bring us to?"

Mycroft can’t imagine which one of them he thinks has lost, when they’re both so disgustingly satisfied in their own filth. "It’s not really been that sort of game."

"Isn’t it always that sort of game?"

"You could have thrown a wrench in the gears whenever you liked, if the mood had taken you. Whether or not you might have won in that case, however, depends on your interpretation."

Sherlock’s hum manages to sound calculating. "Stalemate, then?"

"Yes," Mycroft says. He thinks of all the wonderful, wicked opportunities that lie ahead. "Yes, I should think so."


End file.
